Montana has a new geologic map, the first one since 1955. It was compiled by staff of the Montana Bureau of Mines and Geology using data from hundreds of sources. The Geologic Map of Montana includes three parts. Plate 1 is the geologic map of the state (approx. 4x7ft). Plate 2 provides supporting and complementary information including the correlation chart of surface rocks with generalized lithologic information. The third part is a booklet containing all figures shown on plates 1 and 2, additional figures,The new map is 50×80 inches in size and features the state at a scale of 1:500,000.